Omicron Sagittarius ( ο Sgr ) is a double star in the constellation Sagittarius . It is located at a distance of 142 light years from the Sun [1] , belongs to the spectral class K0 (orange giant ). The apparent magnitude is +3.77. The second component has a visible magnitude of 13 and is located at a distance of 36 arc seconds from the main component.
| Omicron Sagittarius | |||
|---|---|---|---|
| Star | |||
 Position ο Sagittarius in the constellation (image from Celestia ) | |||
| Observational data ( Age J2000.0 ) | |||
| Right ascension | |||
| Declination | |||
| Distance | 142 ± 1 St. years (43.6 ± 0.5 pc ) | ||
| Visible magnitude ( V ) | 3,771 [2] [3] | ||
| Constellation | Sagittarius | ||
| Astrometry | |||
| Radial velocity ( R v ) | 26.1 ± 0.6 [3] km / s | ||
| Own movement (μ) | RA: 76.35 ± 0.31 [3] Dec: −58.12 ± 0.18 [3] | ||
| Parallax (π) | 22.96 ± 0.24 [3] mas | ||
| Absolute magnitude (V) | 0.625 [2] | ||
| Specifications | |||
| Spectral class | K0III | ||
| physical characteristics | |||
| Weight | 2.14 [2] M ☉ | ||
| Temperature | 4759 [2] K | ||
| Metallicity | −0.04 [2] | ||
| |||
| Database Information | |||
| SIMBAD | data | ||
The star is located at a distance of 0.86 degrees north of the ecliptic plane, therefore, star coverings with the moon and, very rarely, planets can occur. The last planet cover occurred on December 24, 1937, when the star was covered with Mercury. The sun does not reach this star a little: the apparent diameter of the sun is about half a degree. [4] The object can be observed almost all night in early July.
Name and etymology
In Chinese astronomy, 建 ( Jiàn ) refers to asterism consisting of stars ο Sagittarius, ξ² Sagittarius , π Sagittarius , 43 Sagittarius , ρ¹ Sagittarius and υ Sagittarius . The star itself ο Sagittarius is called 建 二 Jiàn èr . [five]
Notes
- ↑ 1 2 3 van Leeuwen, F. HIP 93683 . Hipparcos, the New Reduction (2007). Date of treatment December 4, 2009.
- ↑ 1 2 3 4 5 Liu, YJ; Zhao, G .; Shi, JR & Pietrzyński, G. (2007), " The abundances of nearby red clump giants ", Monthly Notices of the Royal Astronomical Society T. 382 (2): 553–66 , DOI 10.1111 / j.1365-2966.2007.11852 .x
- ↑ 1 2 3 4 5 omi Sgr . SIMBAD Center de données astronomiques de Strasbourg . Date of treatment July 30, 2019.
- ↑ In the Sky Earth astronomy reference utility showing the ecliptic and relevant date as at J2000 - present
- ↑ (Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文 教育 資訊 網 2006 年 5 月 11 日